1. Field of the Invention
The present invention relates to a head cleaning system of a video cassette recorder, and more particularly, to a head cleaning system of a video cassette recorder having double need cleaning rollers.
2. Description of the Prior Art
FIG. 1A of the accompanying drawings shows, by way of example, a conventional head cleaning system of a video cassette recorder, in which a head cleaning roller is in contact with a head drum to clean it when a video cassette ape is loaded or unloaded. FIG. 1B also shows the conventional head cleaning system of FIG. 1, in which the head cleaning roller is apart from the head drum during a recording and/or reproducing operation of the video cassette recorder. Referring to FIGS. 1A and 1B, the head drum 1 incorporates a head 2 in its peripheral surface.
A cam 3 is driven by a motor which is not shown. The cam 3 is formed with a guide groove 3a which is eccentric with respect to a camshaft 4, the eccentric guide groove 3a extending counterclockwise and radially. A lever 5 is positioned between the head drum 1 and cam 3, To one end of the lever 5 is secured a sliding pin 7 which engages with the eccentric guide groove 3a, and to the other end of the lever 5 is rotatably arranged a head cleaning roller 6 which cleans the head drum 1. The sliding pin 7 slides clockwise or counterclockwise in the guide groove 3a in accordance with a rotation of the cam 3.
A pivot 8 is disposed between the head cleaning roller 7 and eliding pin 7, and the lever 5 is so mounted as to rotate on the pivot 8 according to the rotation of the cam 3. The lever 5 is tilted near the pivot 8.
When loading or unloading a video cassette tape, the cam 3 rotates clockwise and the sliding pin 7 slides along the guide groove 3a of the cam 3 due to the rotation of the cam 3, as shown in FIG. 1A. Accordingly, the lever 5 rotates in a direction shown by an arrow A on the pivot 8, thereby to cause the head cleaning roller 6 to be in contact with the head drum 1 so that the head drum 1 can be cleaned by the cleaning roller 6.
Meanwhile, during a recording or reproducing operation of the video cassette recorder, the cam 3 rotates counterclockwise as shown in FIG. 1B and the sliding pin 7 slides in a direction opposite to that shown in FIG. 1A along the guide groove 3a by virtue of the rotation of the cam 3.
Accordingly, the lever 5 rotates in a direction shown by an arrow B on the pivot 8, thereby to cause the cleaning roller 6 to be apart from the head drum 1.
However, the conventional head cleaning system equipped with afore-mentioned structure has a problem in that when loading or unloading a video tape, since only a single cleaning roller 6 comes in contact with the head drum 1 to clean it, the cleaning roller 6 is easily contaminated by the head drum 1 and moreover, if a video cassette recorder has been used for a long period, the head drum 1 is not cleaned but contaminated by the contaminated head cleaning roller 6 so a desired cleaning for the head drum cannot be accomplished.
In addition, the head cleaning system has deficiency in that due to the cleaning by one cleaning roller 6 only, the cleaning roller 6 is easily worn.